Boring-tool.



PATBNTED APR. 7, 19083 0. TACK. BORING TOOL.

1 APPLICATION FILED AUG. 12. 1905.

UNITED STATES PATENT OFFICE.

OSCAR TACK. OF NEWARK- NEW JERSEY, ASSIGSOR TO TOWER YORK, N. Y., A CORPOR-XTION OF NEW & LYON COMPANY; GF NEW YORK.

BORING-TOOL.

Specification of Letters Patent.

rammed April 7,1908.

Application filed August 12, 1905. SerialNo. 273.857;

To all whom it may concern:

.Be it known that I, OSCAR TACK, residing at Newark, 1n the county ofEsseX and State of ew' Jersey, have invented certain new, and useful Improvements 1n Boring-Tools, of

' which the following is a full, clear, and exact description, such as will enable others skilled in the art to which it appertains to make and use the same. AIY'IIIVGIllDlOil relates to boring tools and, n a more specific relation thereof, to expansion or expansiblebits adapted for boring wood.

One of the-objects contemplated is the pro-v vision of a tool of the class described'which shall be characterized by ease of manipulation in operation.

' Another and more specific object is the prevention of crowding or dragging the material being cut during the. operation ofthe" tool, and the attainment of an efficient shearing out without impairing the general efliciency ofthe tool. i

The invention accordingly consists in the features of construction, combinations of elements'and arrangement of parts which will be exemplified in the device hereinafter describedand the scope of the application of which will beindicated in the following claims.-

In the accompanying drawing, wherein 1S 3 shown the preferred embodiment of my inventio'nfFigure' 1 is a front elevation, Fig. 2 is a side elevation, Fig. 3 is a bottom plan View, Fig. 4 is a perspective of the eXpa-nsible cutter- Similar reference characters refer to similar parts throughout the several views of the drawing.

In order to more clearly understand the character of my invention, it should be noted V that-tools of the general class described have a tendency to crowd or'bind-during operation,

and" the chi s being'severed-tend to become wedged, wit the result that theparts of the 'bit are liable to frequent displacement.

When the main cutting edge of an adjustable cutter is located either forward or rearwardoi an axial plane of the bit head, the

cutter is either forced or dragged, that is, it is either working ahead orbehind the other elements of the tool. ficulty of operation and decreases the effi ciency of the tool. More metal, proportionately, must accordingly be provided and the bility' of This increases the difexpense of manufacture is correspondingly increased. The present invention, however,

provides a construction which obviates the defects'pointed out and accomplishes, among others, the objects indicated.

Referring now to Fig. '1, the illustrative embodiment of my invention is shown in operative position. To-the bit shank-1 located below the bit'head 2 is adjustably secured by wedge plate-3 an adjustable cutter 4 having two edged spurs -5 and 6 mounted thereon.

The spur 6 is ordinarily mounted upon the cutterat a point where it will provide for severing and dividing'the chips tobe cut by the wedging and to insure theirfree dischar e." A lead screw 7 1s screw-threaded into the bit head. Plate 3 is held in engagement'with the'shank 1 of the cutter'4, as appears more clearly in Fig. 2,'by any suitable means, as a screw 8'. A projection or lug 9v (Fig. 1) upon the plate 3 is adapted to register and'engage cutter 4 so. asJto minimize any crowding or 73 with a notch 10in the shank,.to prevent relative lateral movement between i the said plate and shank and thus the various members are loose and being adjusted or tightened.

Referring now to Fig. 3, the relativeare rangen ent of parts desired for the attainprevent thepossi so displacementof the cutter 4 while ment of certain of tmtemplated I by my invention, is illustrated. The main cutting edge b-lof the cutter 4 isshown in an axial plane ofjhe bit head 2. The'point c ofthe cutting lip-11 on the bit head 2 is preferably located in the same plane and the lower cutting point (i (Fig. 4) of the spur 5 is like- I head 2.

Although the use of the construction herein disclosed is believed to be sufliciently apparent, a general statement of the "manner of use, taken in connection with. certain of the purposes and advantages contemplated and attained, as well as of the disadvantages overcome, may be made.

its

l/Vhen the bit is being operated, it vdll be seen, considering Fig. of the drawing, that:

if the main cutting edge of the cutter were or rearward of an axial plane of the bit head, the revolution of the latter in operation would produce either driving out. By locating the main cutting edge of the ads, justable cutter in an axial plane of thb bit head the cutter does not work ahead of nor out of unison with-the other parts of the bit.

a normal shearing out which is much more 'efiicient than the usual extreme shearing or driving cut. The, outer spur upon the cutter having its lower; 'most or extreme cutting point in an axial plane, severe the wood to be removed at the I same time the Wood which has been cut by.

. said spur is being cut located either forward an extreme shearing cut, or a This arrangement produces edge of the cutter. upon the cutter head divides are subjected to a minimum strain.

results in. easier manipulation,

class described from relatively less metal.

a point near the spur cutting edge of the spur.

Itwill accordingly be seen that the attains, among others,

defects and objections indicated.

The fact, which is articularly applicable this general character, should be obvious, that various changes in detail and in construction and formation of parts, may be made; that elements which apparently vary from those specified herein be substituted andotlier changes made in the construction illustrated, which, while the appearance thereof, would still involve the ideas and appropriate the utilities su ested by the invention disto constructions of may materially changing closed herein.

by the main cutting The spur 6 mounted between the working extremity thereof and the periphery of the bit the chip to be loosened, and thus minimizes the tendency to wedge- This feature of locating the principal cutting edges and points in an axial plane of the bit head results in a construction wherein all the parts Work inuniformity with each other and This less liability of the parts to get out of placement, and the possibility of producing an efficient tool of the res ent invention provides a construction winch the ob ects and advantages herein specified and obviates the seam I desire it also to be understood that the language used in the following claims is intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invenbe said to fall therebetween.

Having described my invention, what I claim as new and desire to secure by Letters Patent, is

bit head, an adjustable cutter mounted thereon, and a plurality of edged spurs depending from said cutter, one of said spurs and of the main cutting edge of said-cutter, and between the cutting extremity of said cutter and the periphery of said bit head.

2. In an ex ansion bit, in combination, a bit head, an a justable cutter mounted thereon, and a plurality of edged spurs depending from said cutter, one of said s u'rs being located rearward of the other thereof and of the main cutting edge of said cutter and between the cutting extremity of said cutter cutting edge of said cutter being located in a diametric plane of said bit head.

3. In an ex ansion bit, in combinatioma bit head, an a justable cutter mounted thereon, and a plurality of edged spurs depending from said cutter, one of said spurs being losaid cutter and between the cuttingJ-eX- tremity thereof and the eriphery of said bit head, the main cutting e ge of said cutter be ing located in an axial plane of said bit head,

a portion of the periphery of the latter being cut away opposite said latter spur to form a channel for chips.

l. In an expansion bit head, an adjustable cutter mounted there on, and a plurality of edged spurs depending from said cutter, one of said's urs being lo cat-ed rearward of the main c tting edge of said cutter and betweenthe cutting extreinity thereof and the periphery of said bit head, a portion of the periphery of the latter being cut away opposite said latter spur to form channel for chips.

in testimony whereof I atlix my signature,

in the presence of two witnesses.

Giiflziii TACK. Witnesses:

C. TNARFIELD, An'rnun G. Fauna.

and the periphery of said bit head, the main cated rearward of the main'cuttingedge of bit, in combination,

tion which, as a matter of language, might 1. In anexpansion bit, in pgrnbmatiom a eing located rearward of the other thereof, 

